39=X(x+5)

Solution for 39=X(x+5) equation:

39=X(X+5)

We move all terms to the left:

39-(X(X+5))=0


We calculate terms in parentheses: -(X(X+5)), so:

X(X+5)

We multiply parentheses

X^2+5X

Back to the equation:

-(X^2+5X)


We get rid of parentheses

-X^2-5X+39=0

We add all the numbers together, and all the variables

-1X^2-5X+39=0

a = -1; b = -5; c = +39;
Δ = b2-4ac
Δ = -52-4·(-1)·39
Δ = 181
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-5)-\sqrt{181}}{2*-1}=\frac{5-\sqrt{181}}{-2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-5)+\sqrt{181}}{2*-1}=\frac{5+\sqrt{181}}{-2}
$